1. Field of the Invention
This invention is relates to new therapeutic applications of garlic extracts containing allicin, diallyl disulfide, trisulfide, etc., and more specifically this application relates to the use of these extracts against human prostate gland and bladder tumors. The therapeutic applications relate to the strong immunostimulation mediated anticancer effects elicited by allicin, diallyl disulfide, and diallyl trisulfide in garlic extracts, which induce programmed prostate and bladder cancer cell death.
2. Description of the Prior Art
Prostate cancer death is prevalent in the U.S. and Europe. Prostate cancer is the second largest cause of cancer death among the male population in these countries. In Korea, as the elderly male population increases and as more advanced diagnostic techniques for detecting prostate cancers are imported into the country, the incidence of detected prostate cancers within Korea is expected to increase. The incidence of prostate cancer within Korea is also expected to rise because of dramatic changes in dietary habits, including the increased consumption of dairy products, which are closely associated with the number of male prostate cancer patients and an increase in male mortality due to prostate cancer. Thus, prostate cancer in Korea is expected to become one of the major socially important diseases.
Unfortunately, when many patients are diagnosed with prostate cancer, prostate tumors have already metastasized to bone marrow and lymph nodes. In such cases, the only treatment mode is hormonal therapy (either radical orchiectomy of both testes and/or continued injection of LHRH analogues). Most patients respond well to primary treatment, however, more than half of the patients develop resistance to hormonal treatment and unfortunately, these patients die within a year to a year and a half. Consequently, it was very much desired to find new therapeutic regimens or ways to increase the quality of life for patients who are resistant to hormonal therapy. Effective new therapeutic regimens have not yet been discovered. Furthermore, the discovery of preventive therapeutic agents that significantly reduce the incidence of prostate cancer without serious side effects, will become highly desired.
The etiology of malignant bladder cancers are attributed to long term exposure to cigarette smoke and/or environmental carcinogens. In Korea, the incidence of bladder cancer is the highest among urinary and reproductive tract cancers and is one of the top five most prevalent types of cancers among males. Male bladder cancer incidence is expected to increase and likewise, the mortality rate is expected to increase. Bladder cancers are classified into 3 categories based on their progression. The three categories are superficial, invasive, and metastatic cancers. The incidence of superficial bladder cancer is the highest, but even if this category of bladder cancer is found at an early stage, resection of the urethra and bladder are required. Additionally, even if all visible tumors are removed by resection, the reoccurrence rate is still as high as 50xcx9c70%. Repeated resections lead to a higher incidence of complication such as urethra stricture, bladder perforation, and severe inflammation. In recent times, in attempt to reduce recurrence of bladder tumors, chemotherapeutic agents or immunomodulators are often prescribed following the initial tumor resection. Nonetheless, extremely bloody urine and inflammation of the urethra ensue, which further complicates treatment to stop the continued progression of bladder cancers. Furthermore, in the case of invasive bladder cancers, a radical resection of the bladder is required which requires the use of an artificial bladder. This causes not only severe disruption to the daily livelihood of patients, but also often leads to postsurgical complications.
When patients are diagnosed with metastasized bladder cancers, the only treatment left is to treat the patients with aggressive chemotherapy, but this leads to severe complications. Even with the use of aggressive chemotherapy, the prognosis of patients with metastasized bladder cancers is not very good. For this reason, it is of vital importance that more effective therapeutic agents or highly effective preventive agents for use against the occurrence of bladder cancers need to be developed. Especially, it is highly desirable to develop effective chemopreventive agents that do not have severe side effects or an unreasonable cost.
The inventors sought to find either therapeutic chemicals or the extracts of natural plants to provide new alternative therapeutic or preventive agents for the treatment of prostate and bladder cancer. Treatments that selectively eradicate both prostatic and bladder cancer cells were specifically sought. We were able to discover and complete this invention as a result of our experimental research showing that garlic extracts clearly possesses chemopreventive effects, and also that they induce programmed cancer cell death in both prostate and bladder cancer cells.
Furthermore, the objective of the invention is to propose that garlic extracts containing allicin are highly effective preventive and/or chemotherapeutic agents against prostatic and bladder cancers. The other objective of this invention is to show that compositions of garlic extracts containing allicin are very effective chemotherapeutic agents for use against prostatic and bladder cancers.
The object of the invention previously described is accomplished by experimentally confirming that garlic extracts containing allicin, diallyl disulfide, diallyl trisulfide, and inclusive of other effective compounds are highly effective chemopreventive and/or chemotheraputic agents in experimental mice bearing human prostatic and bladder tumors.
A chemopreventive and chemotherapeutic composition for human prostate and human bladder cancers comprising allicin-containing garlic extracts isolated and purified from garlic, is described in detail below.